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Marlborough is a town in Hartford county in Connecticut. It was formed in 1803 from the following town or towns: Colchester/Glastonbury/Hebron. Marlborough is a part of the Marlborough probate district and has been since 1846. Colchester was/were the previous chronological district or districts. For more information, contact the county at 26 N. Main St./P.O. Box 29 Marlborough 06447. On the attached map, Hartford is located at F4.